'use client';

import { useState, useMemo, useEffect } from 'react';
import { ChevronDown, ChevronUp, Phone, X } from 'lucide-react';
import { useSearchParams } from 'next/navigation';
import Link from 'next/link';
import { Product } from '@/content/products';
import { ProductCard } from './ProductCard';
import { companyDetails } from '@/content/company';

interface ProductsGridProps {
  products: Product[];
  brands: string[];
}

const PER_PAGE = 24;

// Parsuj moc chłodniczą — zwróć wartość MAX z zakresu
function parseMocMax(val: string): number | null {
  if (!val) return null;
  const nums = val.replace(/[^\d,.-]/g, ' ').split(/[\s\/–-]+/).map(s => parseFloat(s.replace(',', '.'))).filter(n => !isNaN(n));
  return nums.length > 0 ? Math.max(...nums) : null;
}

// Parsuj hałas — zwróć wartość MIN z zakresu
function parseHalasMin(val: string): number | null {
  if (!val) return null;
  const nums = val.match(/\d+/g);
  return nums ? Math.min(...nums.map(Number)) : null;
}

// Mapowanie wykończenia na grupy kolorystyczne
function mapWykonczenie(val: string): string {
  const v = val.toLowerCase();
  if (v.includes('white') || v === 'biały') return 'Biały';
  if (v.includes('black') || v === 'czarny' || v === 'dark' || v.includes('satin')) return 'Czarny';
  if (v.includes('silver') || v === 'srebrny') return 'Srebrny';
  if (v.includes('gold') || v === 'złoty' || v === 'champagne') return 'Złoty';
  if (v.includes('graphite') || v.includes('grey') || v.includes('gray')) return 'Grafitowy';
  if (v.includes('wood') || v.includes('fabric') || v.includes('textile') || v.includes('leather') || v.includes('stone') || v.includes('mirror') || v.includes('caramel') || v.includes('navy') || v.includes('miedziany') || v === 'beige stone') return 'Inne';
  if (v === 'matt' || v === 'shiny') return 'Biały';
  return 'Inne';
}

const COLOR_GROUPS = ['Biały', 'Czarny', 'Srebrny', 'Złoty', 'Grafitowy', 'Inne'];

// Buckety wielkości pomieszczenia → zakres mocy kW
const ROOM_BUCKETS = [
  { label: 'do 20 m²', min: 0, max: 2.5 },
  { label: '21–35 m²', min: 2.5, max: 3.5 },
  { label: '36–50 m²', min: 3.5, max: 5.0 },
  { label: '51–70 m²', min: 5.0, max: 7.0 },
  { label: 'powyżej 70 m²', min: 7.0, max: 99 },
];

interface AccordionProps {
  title: string;
  children: React.ReactNode;
  defaultOpen?: boolean;
}

function Accordion({ title, children, defaultOpen = true }: AccordionProps) {
  const [open, setOpen] = useState(defaultOpen);
  return (
    <div className="border-b border-border pb-4 mb-4">
      <button
        onClick={() => setOpen(!open)}
        className="flex items-center justify-between w-full text-left"
      >
        <span className="text-sm font-bold text-primary font-heading">{title}</span>
        {open ? <ChevronUp className="size-4 text-text-muted" /> : <ChevronDown className="size-4 text-text-muted" />}
      </button>
      {open && <div className="mt-3">{children}</div>}
    </div>
  );
}

export function ProductsGrid({ products, brands }: ProductsGridProps) {
  const searchParams = useSearchParams();
  const urlSearch = searchParams.get('search') || '';
  const urlBrand = searchParams.get('brand') || '';
  const urlCategory = searchParams.get('category') || 'all';

  const [category, setCategory] = useState<'all' | 'scienne' | 'multisplit' | 'podlogowe' | 'jednostka-scienna' | 'pompy-ciepla'>(
    urlCategory as 'all' | 'scienne' | 'multisplit' | 'podlogowe' | 'jednostka-scienna' | 'pompy-ciepla'
  );
  const [selectedBrands, setSelectedBrands] = useState<string[]>(urlBrand ? [urlBrand] : []);
  const [searchQuery, setSearchQuery] = useState(urlSearch);
  const [priceMin, setPriceMin] = useState('');
  const [priceMax, setPriceMax] = useState('');
  const [selectedRooms, setSelectedRooms] = useState<string[]>([]);
  const [selectedColors, setSelectedColors] = useState<string[]>([]);
  const [selectedUnitCounts, setSelectedUnitCounts] = useState<number[]>([]);
  const [halasMin, setHalasMin] = useState(15);
  const [halasMax, setHalasMax] = useState(50);
  const [page, setPage] = useState(1);
  const [mobileSidebarOpen, setMobileSidebarOpen] = useState(false);

  useEffect(() => {
    const timer = setTimeout(() => {
      setSearchQuery(urlSearch);
      setSelectedBrands(urlBrand ? [urlBrand] : []);
      if (urlCategory !== 'all') {
        setCategory(urlCategory as 'scienne' | 'multisplit' | 'podlogowe' | 'jednostka-scienna' | 'pompy-ciepla');
      } else {
        setCategory('all');
      }
      setPage(1);
    }, 0);
    return () => clearTimeout(timer);
  }, [urlSearch, urlBrand, urlCategory]);

  const toggleBrand = (b: string) => {
    setSelectedBrands(prev => prev.includes(b) ? prev.filter(x => x !== b) : [...prev, b]);
    setPage(1);
  };

  const toggleRoom = (r: string) => {
    setSelectedRooms(prev => prev.includes(r) ? prev.filter(x => x !== r) : [...prev, r]);
    setPage(1);
  };

  const toggleColor = (c: string) => {
    setSelectedColors(prev => prev.includes(c) ? prev.filter(x => x !== c) : [...prev, c]);
    setPage(1);
  };

  const toggleUnitCount = (uc: number) => {
    setSelectedUnitCounts(prev => prev.includes(uc) ? prev.filter(x => x !== uc) : [...prev, uc]);
    setPage(1);
  };

  const filtered = useMemo(() => {
    return products.filter(p => {
      // Wyszukiwanie tekstowe
      if (searchQuery) {
        const sq = searchQuery.toLowerCase();
        if (!p.name.toLowerCase().includes(sq) && !p.brand.toLowerCase().includes(sq)) {
          return false;
        }
      }

      if (category !== 'all' && p.category !== category) return false;

      if (selectedBrands.length > 0 && !selectedBrands.includes(p.brand)) return false;

      const pMin = priceMin ? parseInt(priceMin) : null;
      const pMax = priceMax ? parseInt(priceMax) : null;
      if (p.price !== null) {
        if (pMin && p.price < pMin) return false;
        if (pMax && p.price > pMax) return false;
      }

      // Wielkość pomieszczenia → moc
      if (selectedRooms.length > 0) {
        const moc = parseMocMax(p.specs['Moc chłodnicza'] || '');
        if (moc === null) return false;
        const matches = selectedRooms.some(r => {
          const bucket = ROOM_BUCKETS.find(b => b.label === r);
          return bucket ? moc >= bucket.min && moc < bucket.max : false;
        });
        if (!matches) return false;
      }

      // Hałas
      if (halasMin > 15 || halasMax < 50) {
        const h = parseHalasMin(p.specs['Hałas wewnątrz (dB)'] || '');
        if (h !== null && (h < halasMin || h > halasMax)) return false;
      }

      // Kolor
      if (selectedColors.length > 0) {
        const wyk = p.specs['Wykończenie'] || '';
        const group = mapWykonczenie(wyk);
        if (!selectedColors.includes(group)) return false;
      }

      // Liczba jednostek wewn. (multisplit)
      if (selectedUnitCounts.length > 0) {
        const unitsStr = p.specs['Liczba jednostek wewn.'];
        if (!unitsStr) return false;
        const units = parseFloat(unitsStr);
        if (!selectedUnitCounts.includes(units)) return false;
      }

      return true;
    });
  }, [products, category, selectedBrands, priceMin, priceMax, selectedRooms, halasMin, halasMax, selectedColors, selectedUnitCounts, searchQuery]);

  const totalPages = Math.ceil(filtered.length / PER_PAGE);
  const paginated = filtered.slice((page - 1) * PER_PAGE, page * PER_PAGE);

  // Liczniki per brand (dla aktualnych filtrów bez filtra marki)
  const brandCounts = useMemo(() => {
    const counts: Record<string, number> = {};
    products.forEach(p => {
      if (category !== 'all' && p.category !== category) return;
      counts[p.brand] = (counts[p.brand] || 0) + 1;
    });
    return counts;
  }, [products, category]);

  // Liczniki per room bucket
  const roomCounts = useMemo(() => {
    const counts: Record<string, number> = {};
    products.forEach(p => {
      if (category !== 'all' && p.category !== category) return;
      const moc = parseMocMax(p.specs['Moc chłodnicza'] || '');
      if (moc === null) return;
      ROOM_BUCKETS.forEach(b => {
        if (moc >= b.min && moc < b.max) {
          counts[b.label] = (counts[b.label] || 0) + 1;
        }
      });
    });
    return counts;
  }, [products, category]);

  // Liczniki per liczba jednostek wewn.
  const unitCountsAgg = useMemo(() => {
    const counts: Record<number, number> = {};
    products.forEach(p => {
      if (category !== 'all' && p.category !== category) return;
      const unitsStr = p.specs['Liczba jednostek wewn.'];
      if (unitsStr) {
        const units = parseFloat(unitsStr);
        if (!isNaN(units)) {
          counts[units] = (counts[units] || 0) + 1;
        }
      }
    });
    return counts;
  }, [products, category]);

  const resetAll = () => {
    setCategory('all');
    setSelectedBrands([]);
    setSearchQuery('');
    setPriceMin('');
    setPriceMax('');
    setSelectedRooms([]);
    setSelectedColors([]);
    setSelectedUnitCounts([]);
    setHalasMin(15);
    setHalasMax(50);
    setPage(1);
  };

  const hasFilters = category !== 'all' || selectedBrands.length > 0 || searchQuery !== '' || priceMin || priceMax || selectedRooms.length > 0 || selectedColors.length > 0 || selectedUnitCounts.length > 0 || halasMin > 15 || halasMax < 50;

  const sidebarContent = (
    <aside className="w-full">
      <Accordion title="Klimatyzatory">
        <ul className="flex flex-col gap-2">
          {[
            { val: 'all', label: 'Wszystkie' },
            { val: 'scienne', label: 'Ścienne split' },
            { val: 'multisplit', label: 'Multisplit' },
            { val: 'pompy-ciepla', label: 'Pompy ciepła' },
          ].map(opt => (
            <li key={opt.val}>
              <button
                onClick={() => { setCategory(opt.val as typeof category); setPage(1); }}
                className={`flex items-center gap-2.5 text-sm w-full text-left py-0.5 transition-colors ${
                  category === opt.val ? 'text-primary font-semibold' : 'text-text-muted hover:text-primary'
                }`}
              >
                <span className={`size-3 rounded-full border-2 shrink-0 ${
                  category === opt.val ? 'border-accent bg-accent' : 'border-border'
                }`} />
                {opt.label}
                <span className="ml-auto text-xs bg-slate-100 rounded-full px-1.5 py-0.5 text-text-muted">
                  {opt.val === 'all' ? products.length : products.filter(p => p.category === opt.val).length}
                </span>
              </button>
            </li>
          ))}
        </ul>
      </Accordion>

      <Accordion title="Marka">
        <ul className="flex flex-col gap-2">
          {brands.map(b => (
            <li key={b}>
              <label className="flex items-center gap-2.5 cursor-pointer group">
                <input
                  type="checkbox"
                  checked={selectedBrands.includes(b)}
                  onChange={() => toggleBrand(b)}
                  className="sr-only"
                />
                <span className={`size-4 rounded border-2 shrink-0 flex items-center justify-center transition-colors ${
                  selectedBrands.includes(b)
                    ? 'bg-accent border-accent'
                    : 'bg-white border-slate-300 group-hover:border-accent'
                }`}>
                  {selectedBrands.includes(b) && (
                    <svg viewBox="0 0 10 8" className="size-2.5" fill="none">
                      <path d="M1 4L3.5 6.5L9 1" stroke="white" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round"/>
                    </svg>
                  )}
                </span>
                <span className={`text-sm transition-colors ${selectedBrands.includes(b) ? 'text-primary font-medium' : 'text-text-muted group-hover:text-primary'}`}>
                  {b}
                </span>
                <span className="ml-auto text-xs text-text-muted">
                  {brandCounts[b] || 0}
                </span>
              </label>
            </li>
          ))}
        </ul>
      </Accordion>

      {/* Ilość jednostek wewnętrznych */}
      {(category === 'all' || category === 'multisplit') && (
        <Accordion title="Ilość jednostek wewn.">
          <ul className="flex flex-col gap-2">
            {[1, 2, 3, 4, 5, 6, 7, 8, 9].map(uc => {
              if (unitCountsAgg[uc] === undefined && !selectedUnitCounts.includes(uc)) return null;
              return (
                <li key={uc}>
                  <label className="flex items-center gap-2.5 cursor-pointer group">
                    <input
                      type="checkbox"
                      checked={selectedUnitCounts.includes(uc)}
                      onChange={() => toggleUnitCount(uc)}
                      className="sr-only"
                    />
                    <span className={`size-4 rounded border-2 shrink-0 flex items-center justify-center transition-colors ${
                      selectedUnitCounts.includes(uc)
                        ? 'bg-accent border-accent'
                        : 'bg-white border-slate-300 group-hover:border-accent'
                    }`}>
                      {selectedUnitCounts.includes(uc) && (
                        <svg viewBox="0 0 10 8" className="size-2.5" fill="none">
                          <path d="M1 4L3.5 6.5L9 1" stroke="white" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round"/>
                        </svg>
                      )}
                    </span>
                    <span className={`text-sm transition-colors ${selectedUnitCounts.includes(uc) ? 'text-primary font-medium' : 'text-text-muted group-hover:text-primary'}`}>
                      {uc} {uc === 1 ? 'jednostka' : uc >= 2 && uc <= 4 ? 'jednostki' : 'jednostek'}
                    </span>
                    <span className="ml-auto text-xs text-text-muted">
                      {unitCountsAgg[uc] || 0}
                    </span>
                  </label>
                </li>
              );
            })}
          </ul>
        </Accordion>
      )}

      <Accordion title="Cena (zł)">
        <div className="flex items-center gap-2">
          <input
            type="number"
            placeholder="od"
            value={priceMin}
            onChange={e => { setPriceMin(e.target.value); setPage(1); }}
            className="w-full border border-border rounded-lg px-3 py-2 text-sm text-primary focus:border-accent outline-none"
          />
          <span className="text-text-muted shrink-0">–</span>
          <input
            type="number"
            placeholder="do"
            value={priceMax}
            onChange={e => { setPriceMax(e.target.value); setPage(1); }}
            className="w-full border border-border rounded-lg px-3 py-2 text-sm text-primary focus:border-accent outline-none"
          />
        </div>
      </Accordion>

      {/* Wielkość pomieszczenia */}
      <Accordion title="Wielkość pomieszczenia">
        <ul className="flex flex-col gap-2">
          {ROOM_BUCKETS.map(b => (
            <li key={b.label}>
              <label className="flex items-center gap-2.5 cursor-pointer group">
                <input
                  type="checkbox"
                  checked={selectedRooms.includes(b.label)}
                  onChange={() => toggleRoom(b.label)}
                  className="sr-only"
                />
                <span className={`size-4 rounded border-2 shrink-0 flex items-center justify-center transition-colors ${
                  selectedRooms.includes(b.label)
                    ? 'bg-accent border-accent'
                    : 'bg-white border-slate-300 group-hover:border-accent'
                }`}>
                  {selectedRooms.includes(b.label) && (
                    <svg viewBox="0 0 10 8" className="size-2.5" fill="none">
                      <path d="M1 4L3.5 6.5L9 1" stroke="white" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round"/>
                    </svg>
                  )}
                </span>
                <span className={`text-sm transition-colors ${selectedRooms.includes(b.label) ? 'text-primary font-medium' : 'text-text-muted group-hover:text-primary'}`}>
                  {b.label}
                </span>
                <span className="ml-auto text-xs text-text-muted">
                  {roomCounts[b.label] || 0}
                </span>
              </label>
            </li>
          ))}
        </ul>
        <p className="text-xs text-text-muted mt-2">Szacunkowo: 10 m² = 1 kW mocy chłodniczej</p>
      </Accordion>

      {/* Głośność */}
      <Accordion title={`Głośność wewnętrzna (dB) — ${halasMin}–${halasMax} dB`}>
        <div className="flex flex-col gap-4 px-1">
          <div className="flex flex-col gap-1.5">
            <div className="flex items-center justify-between">
              <span className="text-xs text-text-muted">od</span>
              <span className="text-xs font-bold text-primary bg-accent/10 px-2 py-0.5 rounded-md">{halasMin} dB</span>
            </div>
            <input
                type="range"
                min={15} max={50}
                value={halasMin}
                onChange={e => { setHalasMin(Math.min(Number(e.target.value), halasMax - 1)); setPage(1); }}
                className="range range-xs range-accent w-full"
              />
          </div>
          <div className="flex flex-col gap-1.5">
            <div className="flex items-center justify-between">
              <span className="text-xs text-text-muted">do</span>
              <span className="text-xs font-bold text-primary bg-accent/10 px-2 py-0.5 rounded-md">{halasMax} dB</span>
            </div>
            <input
                type="range"
                min={15} max={50}
                value={halasMax}
                onChange={e => { setHalasMax(Math.max(Number(e.target.value), halasMin + 1)); setPage(1); }}
                className="range range-xs range-accent w-full"
              />
          </div>
        </div>
      </Accordion>

      <Accordion title="Kolor dominujący">
        <ul className="flex flex-col gap-2">
          {COLOR_GROUPS.map(c => (
            <li key={c}>
              <label className="flex items-center gap-2.5 cursor-pointer group">
                <input
                  type="checkbox"
                  checked={selectedColors.includes(c)}
                  onChange={() => toggleColor(c)}
                  className="sr-only"
                />
                <span className={`size-4 rounded border-2 shrink-0 flex items-center justify-center transition-colors ${
                  selectedColors.includes(c)
                    ? 'bg-accent border-accent'
                    : 'bg-white border-slate-300 group-hover:border-accent'
                }`}>
                  {selectedColors.includes(c) && (
                    <svg viewBox="0 0 10 8" className="size-2.5" fill="none">
                      <path d="M1 4L3.5 6.5L9 1" stroke="white" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round"/>
                    </svg>
                  )}
                </span>
                <span className={`text-sm transition-colors ${selectedColors.includes(c) ? 'text-primary font-medium' : 'text-text-muted group-hover:text-primary'}`}>
                  {c}
                </span>
              </label>
            </li>
          ))}
        </ul>
      </Accordion>

      <div className="rounded-xl bg-slate-50 border border-border p-4 text-center mt-2">
        <p className="text-sm font-bold text-primary font-heading mb-3">Potrzebujesz pomocy?</p>
        <a
          href={`tel:${companyDetails.phoneRaw}`}
          className="flex items-center justify-center gap-2 text-primary font-bold text-base hover:text-accent transition-colors"
        >
          <Phone className="size-4 text-accent" />
          {companyDetails.phone}
        </a>
        <p className="text-xs text-text-muted mt-1">{companyDetails.hours}</p>
        <Link href="/kontakt" className="mt-3 w-full btn btn-primary text-white font-bold text-sm py-2">

            Zadaj pytanie
          
</Link>
      </div>
    </aside>
  );

  return (
    <section className="py-8 md:py-12 bg-white">
      <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8">

        <div className="lg:hidden mb-4 flex items-center justify-between">
          <button
            onClick={() => setMobileSidebarOpen(true)}
            className="flex items-center gap-2 px-4 py-2 border border-border rounded-lg text-sm font-medium text-primary hover:border-accent hover:text-accent transition-colors"
          >
            <ChevronDown className="size-4" />
            Filtry {hasFilters && <span className="size-2 rounded-full bg-accent inline-block" />}
          </button>
          <span className="text-sm text-text-muted">{filtered.length} produktów</span>
        </div>

        {mobileSidebarOpen && (
          <div className="fixed inset-0 z-50 lg:hidden">
            <div className="absolute inset-0 bg-black/50" onClick={() => setMobileSidebarOpen(false)} />
            <div className="absolute top-0 left-0 bottom-0 w-80 bg-white overflow-y-auto p-6 shadow-xl">
              <div className="flex items-center justify-between mb-6">
                <span className="font-bold text-primary font-heading">Filtry</span>
                <button onClick={() => setMobileSidebarOpen(false)}>
                  <X className="size-5 text-text-muted" />
                </button>
              </div>
              {sidebarContent}
            </div>
          </div>
        )}

        <div className="flex gap-8">
          <div className="hidden lg:block w-64 shrink-0">
            <div className="sticky top-24 max-h-[calc(100vh-7rem)] overflow-y-auto pr-2">
              {hasFilters && (
                <button
                  onClick={resetAll}
                  className="flex items-center gap-1.5 text-xs text-accent hover:underline mb-4"
                >
                  <X className="size-3" /> Wyczyść filtry
                </button>
              )}
              {sidebarContent}
            </div>
          </div>

          <div className="flex-1 min-w-0">
            <div className="flex items-center justify-between mb-6">
              <span className="text-sm text-text-muted hidden lg:block">{filtered.length} produktów</span>
              {hasFilters && (
                <button onClick={resetAll} className="lg:hidden text-xs text-accent hover:underline flex items-center gap-1">
                  <X className="size-3" /> Wyczyść
                </button>
              )}
            </div>

            {paginated.length > 0 ? (
              <div className="grid grid-cols-1 sm:grid-cols-2 xl:grid-cols-3 gap-5">
                {paginated.map(product => (
                  <ProductCard key={product.slug} product={product} />
                ))}
              </div>
            ) : (
              <div className="text-center py-24">
                <p className="text-text-muted mb-3">Brak produktów dla wybranych filtrów.</p>
                <button onClick={resetAll} className="text-accent hover:underline text-sm">
                  Wyczyść filtry
                </button>
              </div>
            )}

            {totalPages > 1 && (
              <div className="flex justify-center gap-2 mt-12">
                <button
                  onClick={() => { setPage(p => Math.max(1, p - 1)); window.scrollTo(0, 0); }}
                  disabled={page === 1}
                  className="px-4 py-2 rounded-lg border border-border text-sm font-medium text-primary hover:border-accent hover:text-accent disabled:opacity-40 disabled:cursor-not-allowed transition-colors"
                >
                  ← Poprzednia
                </button>
                {Array.from({ length: Math.min(5, totalPages) }, (_, i) => {
                  const p = page <= 3 ? i + 1 : page - 2 + i;
                  if (p < 1 || p > totalPages) return null;
                  return (
                    <button
                      key={p}
                      onClick={() => { setPage(p); window.scrollTo(0, 0); }}
                      className={`px-3 py-2 rounded-lg text-sm font-medium transition-colors ${
                        p === page
                          ? 'bg-accent text-white border border-accent'
                          : 'border border-border text-primary hover:border-accent hover:text-accent'
                      }`}
                    >
                      {p}
                    </button>
                  );
                })}
                <button
                  onClick={() => { setPage(p => Math.min(totalPages, p + 1)); window.scrollTo(0, 0); }}
                  disabled={page === totalPages}
                  className="px-4 py-2 rounded-lg border border-border text-sm font-medium text-primary hover:border-accent hover:text-accent disabled:opacity-40 disabled:cursor-not-allowed transition-colors"
                >
                  Następna →
                </button>
              </div>
            )}
          </div>
        </div>
      </div>
    </section>
  );
}